Sports enthusiasts, particularly bicyclists, are accustomed to carrying a container of water along which they are able to efficiently access "on the run" to quench a thirst. One common form for the container is a flexible plastic bottle with a drinking spout that is manually opened and closed. Conveniently, the drinking spout serves as a mouthpiece for the drinker. Moving the spout to the open position, the cyclist inserts the spout into the mouth and squeezes the bottle, expressing drinking water. Another form is a plastic bottle having a plastic drinking straw. Being always open, the cyclists grips the bottle and, with the straw's end in the mouth, squeezes to express the drinking water.
Further, in my patent U.S. Pat. No. 5,392,968 granted Feb. 28, 1995, entitled Dispensing Closure and Method, hereafter referred to as the "Dark '968 patent", a one-piece molded plastic closure for fluids is described that contains a pivotable spout and a compound diaphragm, the disclosure of which is incorporated herein by reference in its entirety. Among other things evident from inspection of the patent there is also described adaptations to that novel closure structure to enable the closure to serve as such a sport drinking cup cap. The structure illustrated in FIGS. 20 and 21 of that patent employs a flexible thin-walled tubular extension integrally formed on the underside of a more rigid thick walled tubular fluid dispensing spout that lies on the underside of the closure base. With the spout in its open position upstanding fluid confined within the associated container or bottle is dispensed through the spout. When the spout is pivoted down to the closed or sealed position and latched, the flexible tubular extension is pressed against a seal member, a plastic member that depends from the underside of the closure base, collapsing and flattening a portion of the tube to close the fluid passage therethrough.
An alternative embodiment described in the patent combines the one-piece closure with a separate flexible straw to form a two-piece structure. As illustrated in FIGS. 22 and 23 of that patent, a flexible plastic straw is inserted through the rigid spout and extends through the closure base and into the liquid confined in the container. When the pivotable spout is pivoted down to the closed or sealed position and latched, the pivoting spout swings the straw around and bends it, pressing a portion of the straw against a seal member, a plastic member that depends from the underside of the closure base, and, as in the preceding structure, collapses and flattens a portion of the straw to block the fluid passage. Although not specifically illustrated, the foregoing drinking cup caps may include a conventional air vent that extends through the closure base to permit liquids to be more easily sucked from the bottle. The vent allows air to enter the bottle as the liquid is sucked out.
Although novel, the foregoing drinking cup cap structures illustrated did not achieve market acceptance for reasons not herein fully described. The soft tube extending out of the mouthpiece was not acceptable and the lack of a vent in the cap made the drinking cup difficult to use.
Preferably air vents employed in the foregoing drinking cup caps are made sufficiently small in size so that the surface tension of the confined liquid alone would prevent any leakage when the cap was closed. One problem with small sized vents in rigid caps is that the liquid can only be sucked from the container as fast as the exterior air can enter, which is an annoyance to some. Further, because of the varied nature of liquids held in the bottle, such as beverages, juices and water, and to minimize the potential for clogging that vent, wherein operation would be more difficult, particularly for uninformed users who may not understand the purpose of the air vent, the approach taken is to use a much wider vent than would otherwise be necessary. As a consequence, the drinking cup cap would allow some minor leakage, and could not be characterized as leak-proof.
Good hygiene is a concern that is sometimes overlooked. To ensure that the drinking cup is sanitary it should be frequently disassembled and washed. The most widely available drinking cup cap uses a push-pull valve, which is formed of two components. That valve is not designed to be dismantled for cleaning. Therefore, even when the drinking cup and cap are washed in a normal manner, particles of juice or other liquids may remain between the two valve components inside the valve, causing contamination. Other drinking caps, such as those imported from China, are manufactured and assembled from an even larger number of components. One such drinking cup product consists of a cap, a straw, an a rubber tube joining the straw to the spout, and an over cap that, when twisted, closes the valve and encapsulates the spout. That product is not designed for cleaning and is almost impossible to sterilize.
A principal object of my invention is to provide a leakproof drinking cup cap.
Another object of my invention is to provide a leak proof drinking cup that takes advantage of some elements of my prior designs while being more easily manufactured and used.
A further object of my invention is to provide a drinking cup cap that requires less force to unlatch and open making it easier for user's to use a drinking cup "on the run".
And a still further object of my invention is to provide a drinking cup cap that may be easily dissassembled for cleaning.